1. Field of the Invention
The present invention relates to a running gear for rail vehicles. The invention is suitable for, but not restricted to, use in rail vehicles for passenger traffic.
2. Description of the Related Art
EP 0 621 165 B1 describes a running gear for rail vehicles in which a running gear frame is carried via primary springs by the wheels or wheel sets and on which, via secondary springs, the car body of the rail vehicle is supported car via a rocker or directly. The rocker or the car body are connected with respect to the running gear frame by means of shock absorbers damping vertical and rolling movements and by means of at least one rolling support absorbing rolling movements. The latter bears fixed levers which are connected to the rocker or to the car body via pendulum elements mounted in an articulated fashion. At least one of the pendulum elements consists of an actuator which can be acted on in the opposite direction when one transverse end of the rocker or the car body dips or rises. A disadvantage here is that, already at relatively low speed in the curve, an unfavourably high transverse acceleration occurs. In order to avoid this, the speed in the curve must be reduced so that the travelling comfort for passengers does not deteriorate, for example.
A number of other known applications for intellectual property rights may resemble the solution according to the invention in some details but have significant disadvantages with respect to the latter. Examples of this are as follows:
According to DE 1 145 738 the inclination technology is arranged above the secondary spring so that, when travelling through curves, the complete transverse acceleration must be intercepted in the secondary suspension In addition, the inclination movement is not supported by the centrifugal force which acts during travelling through curves;
According to EP 0 287 821, the pendulums are arranged parallel to the secondary spring suspension which results in vertical decoupling of spring movement and inclination. Thus, the air springs, which are arranged laterally as usual, must execute the complete inclination movement which requires a suitable volume and space requirement of the air springs associated therewith as well as a pressure compensating device;
According to U.S. Pat. No. 3,717,104, vertical pendulums are provided which represent a fundamentally unstable arrangement which requires additional spring elements or active control elements. In addition, during travelling through curves, the inclination movement is not supported by the centrifugal force but, on the contrary, the actuators must work against the centrifugal force and in addition the centering springs. Furthermore, the rolling pole located under the vehicle floor results in large transverse movements at the level of the rows of seats which is generally perceived as unpleasant by passengers, as well as the need for a severely restricted clearance profile of the car body.